ubc.cs.JLog.Foundation.jConsultSourceThread Maven / Gradle / Ivy

Go to download
/*
    This file is part of JLog.

    Created by Glendon Holst for Alan Mackworth and the 
    "Computational Intelligence: A Logical Approach" text.
    
    Copyright 1998, 2000, 2002 by University of British Columbia and 
    Alan Mackworth.
    
    This notice must remain in all files which belong to, or are derived 
    from JLog.
    
    Check  or 
     for further information
    about JLog, or to contact the authors.
     
    JLog is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    JLog is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with JLog; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    URLs:  or 
*/
//#########################################################################
//	jConsultSourceThread
//#########################################################################

package ubc.cs.JLog.Foundation;

import java.lang.*;
import java.util.*;
import java.io.PrintWriter;
import ubc.cs.JLog.Parser.*;

/**
* This class implements consulting of a prolog source text.  
* The source is a TextArea, as is the error output.
*  
* @author       Glendon Holst
* @version      %I%, %G%
*/
public class jConsultSourceThread extends jPrologServiceThread
{
 protected iPrologServiceText				source;
 protected PrintWriter						errors;
 protected jPrologServiceBroadcaster 		begin = null,end = null;
  
 public 	jConsultSourceThread(jPrologServices ps,iPrologServiceText s,PrintWriter e)
 {
  super(ps);

  setName("ConsultSourceThread");
 // setPriority(NORM_PRIORITY + 1); //MRJ 2.1 doesn't permit UI interaction with this setting
   
  source = s;
  errors = e;  
 };

 public void 	setListeners(jPrologServiceBroadcaster b,
                                jPrologServiceBroadcaster e,
 				jPrologServiceBroadcaster s)
 {
  setStoppedListeners(s);
  begin = b;
  end = e;
 };

/**
* Performs and controls the entire consultation phase.
* 
*/
 public void 	run()
 {
  if (begin != null)
   begin.broadcastEvent(new jPrologServiceEvent());
  
  errors.println("consulting.");
  errors.flush();
  
  try
  {pParseStream 	parser;
   
   parser = new pParseStream(source.getText(),prolog.getKnowledgeBase(),
                             prolog.getPredicateRegistry(),
                             prolog.getOperatorRegistry());
   
   try
   {
    parser.parseSource(); 
    prolog.getKnowledgeBase().consult();
    
    errors.print("completed.");
    errors.flush();
   }
   catch (SyntaxErrorException e)
   {
    errors.println("SYNTAX ERROR:");
    errors.println(e.toString()+"\n");
    source.setCaretPosition(e.getPosition());
    source.select(e.getPosition(),e.getPosition()+1);
    errors.print("terminated.");
    errors.flush();
	source.requestFocus(); 
   }
   catch (TokenizeStreamException e)
   {
    errors.println("INTERNAL ERROR:");
    errors.println(e.toString()+"\n");
    source.setCaretPosition(e.getPosition());
    source.select(e.getPosition(),e.getPosition()+1);
    errors.print("terminated.");
	errors.flush();
    source.requestFocus(); 
   }
   catch (RuntimeException e)
   {
    errors.println("ERROR:");
    errors.println(e.toString()+"\n");
    errors.print("terminated.");
	errors.flush();
    source.requestFocus(); 
   }
  } 
  catch (ThreadDeath e)
  {
   throw e; // thread death is user controlled
  }
  catch (Error e)
  {
   errors.println("JAVA ERROR:");
   errors.println(e.toString()+"\n");
   errors.print("terminated.");
   errors.flush();
   source.requestFocus(); 
   throw e; 
  }
  finally
  {
   if (allow_release)
    prolog.release();
  
   if (end != null)
    end.broadcastEvent(new jPrologServiceEvent());
  }
 };

 public boolean 	isCurrentlyConsulting()
 {
  return true;
 };
  
/**
* Displays errors and other output that results from consulting the source.
* 
* @param s 		the input string to append to errors. 
*/
 public void 		printOutput(String s)
 {
  errors.print(s);
  errors.flush();
 };
};